Giardia Natural Treatment Protocol

This is a protocol that I heard about many years ago for getting rid of Giardia, and have used many times successfully (and safely) in cats and dogs. 

This protocol utilizes digestive enzymes on an empty stomach. With no food in the system, the digestive enzymes go to work on anything else that might be in the intestines–including parasites. Although it has not been tested with other protozoal parasites, it could theoretically work for Coccidia, Toxoplasma, Cryptosporidia, Neosporum, Tritrichomonas foetus, and similar protozoal parasites.

You’ll need a bottle of digestive enzymes (plant or fungal based) and one or more syringes; you can usually talk your vet into giving you a few 3 or 6 cc syringes (without needles).

Do not use products containing solely animal-based enzymes or pancreas extracts. While such products will not hurt your pet, plant or fungal enzymes are more likely to survive the stomach’s acidic environment, and still be working when they get to their destination.

You can buy enzymes at any health food store, or order online. However, avoid enzymes in combination with herbs or food supplements. The pet product Prozyme works well; or you can use a human supplement such as Source Naturals Daily Essential Enzymes, Jarrow-Zymes Plus, or Enzymatic Therapy’s Mega-Zyme.

If possible, use a product containing protease, amylase, and lipase (some also contain cellulase). These digest protein, starch, and fat, respectively. If you have trouble finding a good combo product, you can theoretically use protease (such as bromelain or papain) alone. However, the results may not be as good.


Enzymes MUST be given on an empty stomach for best results.

Take 1 dose (according to label directions for pet products) or 1 capsule of enzymes (human product) for each animal to be treated. If you’re using a capsule, open it and just use the contents. Do not give the capsule whole; the gelatin in the capsule will interfere with the enzymes’ effects.

Mix the powder or capsule contents with a tiny amount of water to make a slurry. Use the syringe to give the slurry by mouth. In most cases it’s easiest to insert the syringe in the corners of the mouth between or behind teeth and squirt. The mixture does not taste that bad, but some cats are just not gracious about taking meds. So, be careful, but firm.

Give enzymes three times a day. It is not necessary that they be evenly spaced. Before work, after work, and at bedtime is a schedule that works for many people. Give 1/2 to 1 hour before meals.

Round 1

Give one (1) dose of digestive enzymes 1/2 to 1 hour before morning and evening meals, and one (1) dose at bedtime. Take the syringe apart and rinse clean after each dose (otherwise the residue builds up and the plunger will stick). Repeat daily for eight (8) days.


Take a break for 7 days. This allows time for resistant cysts to “hatch.”

Round 2

Repeat digestive enzyme treatment for 7 days.


If you leave food out for your pet 24/7, this protocol will NOT work. Food must be given only in meals, separately from the enzymes (1/2 to 1 hour after the enzymes).

If there is food in the system, the enzymes will digest that instead of the Giardia, and be carried out of the digestive tract with the food. They need time to work, and they need to be all by themselves.

If there is anything else given with the enzymes, such as probiotics or vitamins or flavorings, the enzymes will digest those. However, simple sugars or single amino acids are fine.

Do not try to hide the enzymes in a pill pocket or a piece of cheese – remember, the tummy must be empty!

You may also add enzymes to your pet’s food to improve digestion overall, but mixing enzymes with food will not have any effect on Giardia.

The protocol must be done exactly as written for best results.

You are free to make any additions, substitutions, or changes you want to the protocol, but if you do, then it is no longer the same protocol and it may not work. 



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48 comments for “Giardia Natural Treatment Protocol

  1. jhofve77
    February 29, 2012 at 12:40 pm

    My personal clinical experience with this protocol has been 100% success. However it is not my protocol and I can’t vouch for it or comment on any particular animal’s response to it. Even to Canada. (It’s not about litigiousness, it’s simply illegal to do so for an animal I have not personally seen.) Nevertheless the problem is that part about “I am assuming…” There are 100s of causes for diarrhea besides parasites, so simply ruling out other parasites is not a diagnosis…so again, I must refer you back to your veterinarian. She is the only one qualified to assess your dog.

  2. danag812
    February 29, 2012 at 11:19 am

    Dr. Jean, I appreciate that you cannot offer ‘diagnostic’ information on individual cases…I already have my vet working with me on treating the dog, and she was actually quite open to me trying this natural treatment protocol. Just to clarify, my dog was diagnosed with giargdia and other parasites were ruled out at that time…so, given that giardia can be difficult to treat in some cases, I am assuming that it is STILL giardia that is causing the diarrhea. I only wanted to know what your experience has been, generally speaking, with this treatment protocol…specifically regarding whether not seeing improvement after the first round is ‘normal’…
    If it is not ‘normal’, I am going to seek out another course of treatment for my dog and not let him suffer through two more weeks of loose stools. I know that the US is a very litigious country, but don’t worry about giving me some advice…I am Canadian :) and we don’t act like that…

  3. jhofve77
    February 29, 2012 at 7:52 am

    Hi, I cannot give veterinary advice for an individual case; however, there are 100s of other causes of diarrhea that can exist simultaneously with giardia; please discuss it with your vet.

  4. danag812
    February 28, 2012 at 2:54 pm

    Hi Dr. Jean,
    I have an 11 year old shepherd mix (weighs about 60lbs)who was diagnosed with giardia about 3 weeks ago. We followed the ‘traditional’ medical protocol (panacur for 5 days and flagyl for 10), but to no avail :(
    After digging through the online resources I found your digestive enzyme protocol. I have completed the first 8 days (3 x per day with plant based digestive enzymes) and the results are definitely better than with the antibiotics. BUT…he is still up and down…stools vary from pretty firm and ‘formed’ to ‘fire hose’ (i.e. very watery diarrhea. Anyway, I am just wondering when I can expect to see some consistent improvement? I am just concerned because we are now entering the 7 day ‘rest’ period (no digestive enzyme treatment) and his bowels are very loose :( Is there anything I can do? Should I just ride this out and continue with the protocol? help!
    Thanks so much.

  5. jhofve77
    February 22, 2012 at 1:51 pm

    Sorry, I do not have any further details, nor do I have any comments to make on any particular product or ingredient. I did not create the protocol, it is simply posted exactly the way I learned it, for your information.

  6. Carmen
    February 20, 2012 at 10:17 am

    I don’t believe that this is necessary an ‘alteration’ to the protocol. I’m just wondering about the amount of water. Does it make a difference? (I’m using aprox 1.5cc, as the enzymes are concentrated.)
    And my other questions was in regards to Maltodextrin used as a binder for enzymes. You are very specific about the contents in the enzyme product and I figured I’d ask for more details on that.

  7. jhofve77
    February 20, 2012 at 6:34 am

    Sorry, we cannot comment on individual cases or on any alterations to the protocol as given.

  8. Carmen
    February 18, 2012 at 6:27 pm

    Hello Dr. Hofve,
    I started the enzyme method yesterday to rid my cats of giardia and am already using ‘Lypozyme’ in their raw meals on a daily basis, so I figured I’ll try it for the regimen on empty stomach as well. It’s fungus based and contains:
    Lipase 2,500 FCCLU, Amylase 5,000 DU, Protease 20,000 HUT, and a Proprietary Enzyme Blend 208 mg per capsule.

    The capsules are very small, compared to the enzymes bought at the healthfood store. Due to the small size of the capsules, there is not much content to create a slurry (I picture a ‘slurry’ being a slightly thicker consistency). I fill the content of one capsule into a 3cc syringe, add aprox 1.5cc water and shake it up. Will the amount of water influence the effectiveness, as it’s really watery? Or would I be better off buying a different one at the healthfood store? If so, is it ok to contain maltodextrin? They all contain some sort of binder – I assume beet root powder would be inappropriate though (?). What’s your opinion on this?
    And how would I know how much of those enzymes to give to the cats? (since the listed dosage is for humans)
    Thank you.

  9. jhofve77
    February 7, 2012 at 5:15 am

    Even Panacur must be given for longer to get Giardia. If you want to follow the protocol, please follow it exactly and for the full course, for best results.

  10. Elaine
    February 6, 2012 at 6:06 pm


    I just began your treatment plan a couple of days ago for a seven month old kitten that has tested positive for giardia. The test was taken because of runny, bloody stools. Panacur was prescribed for the usual five days, but the bloody stools continued. Advanced GI profile tests determined that the giardia was still present. The kitten had progressed to not eating and becoming lethargic, so in desperation to help it and with all the vet offices closed over the weekend, I began to look for alternatives and came upon your site. I do a lot of alternative things for myself and was familiar with digestive enzymes, so I thought I would try it. My enzymes however, contained pancreatic ones and others, so I borrowed some plant-based tablets from my neighbor and crushed them. I am very optimistic, because two days later, my kitten is eating again and playing with his toys and most exciting of all, I can’t see any visible blood in his stools for the first time in 2 and a half months! The vet called today suggesting a stronger treatment than Panacur that has side effects but I am going to do the eight days of this first, keeping a watchful eye on him, to see if he continues to improve. By the way, he was a rescue and has had a lot to contend with so far. Shortly, after finding this litter, they became ill with feline distemper with two littermates dying, one surviving without any lasting effects and this poor little guy who has also been diagnosed with cerebellar hypoplasia. As a result of all of his problems, I am reluctant to administer anything to him that could cause him more problems. I’ll keep you posted. Thank you.

    Elaine & Piccolo

  11. Bev
    February 4, 2012 at 9:51 pm

    whatever is was has cleared up and they both have normal digestive systems. Thank you SOOO much for providing this information. I don’t know what the enzymes taste like but they both lapped it up out of the bowls with no urging whatsoever. I don’t think the syringe would have worked with them.

  12. jhofve77
    January 26, 2012 at 4:10 pm

    I can’t advise you; please talk to your veterinarian!

  13. Bev
    January 25, 2012 at 11:16 pm

    I got a kitten from the SPCA and I believe she had Giardia from the onset. It took a few months to diagnose and try a treatment from the vet then I ran across this information. By this time my other cat had the infection as well. I put both of them through the treatment and was so happy when they both had normal “poops”. For about a week, then it went back to very soft with blood. If it didn’t work the first time should I bother trying again or should I go back to the vet for a different medication?

  14. jhofve77
    September 8, 2011 at 12:03 pm

    My understanding is that plant-based enzymes are stable at a much wider range of temperature and pH than pancreatic extracts.

  15. Kerry
    September 8, 2011 at 11:00 am

    Hi, and Thank You for your information for treating Giardia. I have a puppy with it and wanted to better understand why we should not use the enzymes from an animal base or pancreatic base. I will use the plant base but I just wanted to know what the drawbacks are for the other. Thanks so much for your time and information.

  16. jhofve77
    August 3, 2011 at 7:55 am

    Thanks for the reports! When I was in practice I used this protocol on dogs, cats, and kittens, and it worked perfectly…wish I could remember who told me about it so I could thank them too! :)

  17. Snow
    August 2, 2011 at 1:59 pm

    Dr. Hofve, I just wanted to let you know of some enzyme results and to thank you for your work with alternative medicine and pets. There are so few in veterinary practice who use anything other than drug therapy and many of us deeply appreciate other choices!

    I also wanted to make note that I now know of 3 cats (one is mine) whose owners have used the 2 week enzyme protocol for tritrichomonas foetus. One adult cat who had TF for a couple years did not respond. One young cat never had diarrhea again after the enzymes and the 3rd person had to do the protocol twice before totally eliminating the diarrhea. No testing was done following the treatment, but 2 of the cats did respond well as far as symptoms. Thank you again for offering an alternative to the harsh chemical RX.
    Thank you again, Holly

  18. Iride Piechocki
    July 26, 2011 at 6:18 am

    We are trying this protocol with our 5 month newfie mix puppy. He was a rescue from Kentucky and we’ve had him for one month. Had worms and giardia when we got him. Went through two rounds of Pancur and numerous fecal tests. Still had giardia and hadn’t gained ANY weight. (Newfie pups can gain 2-3 lbs a week) Started this protocol on 7/20. First time we’ve seen solid stools and he’s gained 2 pounds. Will keep you posted!

  19. jhofve77
    July 21, 2011 at 5:18 am

    I don’t have any specific product, just that it should be as purely enzymes as possible. Prozyme should work. Just avoid products that contain other stuff…flavorings, probiotics, any kind of food…because you want to reserve the enzymes for only the nasty bugs!

  20. Tereasa
    July 20, 2011 at 6:06 pm

    We added a kitten to our family in March – a Highlander Lynx – and discovered about a month later that she was suffering from Giardia. The vet prescribed flagyl along with a digestive paste and then tested again 14 days later. She was negative for Giardia so it was case closed.

    A few days ago I noticed a discharge from “back there” – not diarheaa but definitely not normal. So, I took her back in. The vet said the test was positive for Giardia again. She was “baffled” by the reinfection after all this time. I spent today cleaning my cat’s room with bleach water from top to bottom, I threw out her old litter box and her bedding and I am having my carpets steam-cleaned tomorrow. I am desperate to figure this out and get these resolved.

    I want to try your regiment. My cat is now on Flagyl again but I will try this too. Can you recommend a specific product or brand? I saw a reference to Prozyme but it was mentioned as if it is not the ideal choice. I will do whatever I can to get this gone for good. Thanks!

  21. jhofve77
    July 18, 2011 at 7:26 am

    Sorry, I cannot give specific advice for individual cases. Please work with your veterinarian to find a program that works.

  22. sharm4wv
    July 16, 2011 at 1:14 pm

    I have two bengal cats that are 1 1/2. They had cocidia when they were little..It cleared up (my cats are inside and outside cats). I kept them inside when they were little to monitor the litter box now they meow to go outside and won’t use the litter box. One of them had an accident in my closet and its back and I had the vet confirm.. They are on Albon( which I hate because its so strong) and are on day three of it…plus one of them has a sinus infection yeah me…so they have to stay on it. They are given 5ml’s for 5 days. my question to you is…if I add your tx…how long should I wait after the albon tx before I start yours…because I know its a resistant strain and its hard to tell how long they have had it…any advice would be great..thank you

  23. jhofve77
    July 4, 2011 at 8:28 am

    The idea is that there is nothing else in the digestive tract, so that the enzymes are free to digest any parasitic organisms that are present. I’m just presenting the protocol as it was taught to me; any alterations are up to you.

  24. M
    July 3, 2011 at 11:08 am

    hello. i have bought the brand “healthy select” digestive enzymes and realized when i came home that it also has probiotics (acidophilus only) my question is, will this brand still work? it has all the necessary plant enzymes and plenty of them but why will it not work with probiotics included? or will it work less? thank you

  25. jhofve77
    May 15, 2011 at 11:47 am

    Hi Rayann, thanks for your comment! It’s human nature to complain when things go wrong and never mention it when it’s right, so I appreciate your feedback! Hundreds of animals have been treated successfully, but of course giardia is not always the only problem (or even the primary problem) they have! Glad it worked for you all! :)

  26. Rayann K.
    May 15, 2011 at 10:39 am


    After reading the comments here and finding no one responding with a positive outcome, I thought I had better write.

    Some time ago my dog came down with a bout of giardia. The meds my vet gave it worked initially but the giardia came back. Since I loathe giving my animals prescription meds (unless it’s life or death and I can find no other alternatives) I began scouring the internet for natural alternatives.

    When I ran across this article I knew I had to try it, since I knew that various kinds of enzymes are used by people in this way to deal with certain kinds of illnesses.

    At the same time, I had been dealing with major stomach issues that I believed were linked to eating undercooked turkey (I was really sick!). Both my issues and the dog’s had been going on for some time and I was desperate for a cure.

    I did the protocol as described (read the article), and both of our issues were resolved doing the two courses of enzymes (two 3-week treatments). I also decided to give them to the cat as she had had tapeworm before and thought it couldn’t hurt to try it for that. The cat loved them by the way and would just lick the slurry out of the syringe which made it easier to give the dog who before seeing the cat like it had been resistant to taking it!

    Anyway, this worked great for me and I am so grateful for finding it here on this site.

  27. jhofve77
    May 4, 2011 at 5:41 am

    One round. If you do it a different way, it may not be effective.

  28. Debbie Owen
    May 3, 2011 at 12:10 pm

    I have 14 dogs with Giardia given to me when I purchased 2 dogs from a kennel in Arkansas.. so now all the dogs have it .. I am getting it somewhat under control. but was wondering will I need to keep doing the 8 days on and 7 days off .. for how long.. can I be doing it too much to cause them to never get their guts right again.. I also have used some enzymes and other stuff that is supposed to get rid of it,, but it hasn’t .. so Iguess I’ve been feeding the giardia when I feed the enzymes and probiotics with food.. now I am going to try your way and see..

  29. jhofve77
    February 21, 2011 at 7:00 pm

    It is not “my” method…my experience with it has been very positive, but I can’t vouch for any changes you want to make.

  30. J Schuster
    February 21, 2011 at 10:59 am

    Thank you for your info. Do you think I could follow your method and also add the grapefruit seed extract to my dogs food at mealtimes? Or could the combination be to intense for my dogs system? Do you know the effective percentage rate for the digestive enzyme method?

  31. jhofve77
    February 21, 2011 at 9:45 am

    Metronidazole and fenbendazole are each only about 70% effective for giardia. I have not used grapefruit seed extract, but I know it is a powerful antibiotic. Enzymes could change the stool consistency temporarily while the system is clearing and rebalancing itself.

  32. J Schuster
    February 21, 2011 at 8:58 am

    I have a 30lb, 6 month old puppy who was diagnosed with giardia at 8 weeks old. She has been treated with metronidazole and/or fenbendazole since diagnoses without success. I have also been giving her 1 Tbl of coconut oil daily. My vet is now recommending that we allow the giardia to run its course and he believes she will out grow it. Since the original diagnosis, I have researched holistic methods and have noticed that grapefruit seed extract is mentioned frequently. Do you have any opinion on grapefruit seed extract, have you ever used it yourself? I am leaning towards your method, but am just trying to educate myself to the best of my ability. (By the way, other than the positive test results she has been asymptomatic. Will the digestive enzymes cause loose stools/diarrhea?) Thank you for your time and any information you may be able to give me.

  33. jhofve77
    February 17, 2011 at 11:49 pm

    I’d suggest waiting at least 4 hours, if he is on a dry food diet, to allow the food to clear the system. Dry food is the hardest to digest and takes more time. If he is eating a raw diet, you could give it sooner (about 2 hours).

  34. tasha bennett
    February 16, 2011 at 12:28 pm

    Good afternoon,
    How soon after my dog eats can I give another dose? Say he eats dinner at 5:00, should I wait a min. amount of time before his “goodnight” dose?

  35. jhofve77
    February 14, 2011 at 6:13 pm

    There are hundreds of possible causes for diarrhea in kittens; please work with your veterinarian to get an accurate diagnosis and treatment plan.

  36. jayne mcintyre
    February 13, 2011 at 7:18 pm

    So, we tried three rounds of your prescribed treatment for giardia, with no appreciable results. This 10 month old kitten still has chronic diarrhea. What a mess… very foul smelling. Do you have any further suggestions on what we might try with the kitten? We would like to get this figured out ASAP. Please help.

  37. jhofve77
    January 16, 2011 at 10:40 pm

    I can’t give advice for a particular case, so I would strongly recommend that you work with your veterinarian, or with a holistic vet who can address her multiple problems in a comprehensive manner. I would not add or change anything in her current treatment without close monitoring by a vet. To find a holistic vet in your area, check

  38. Adelynn Tan
    January 16, 2011 at 9:39 am

    is giving digestive enzymes (that include amylase) on an empty stomach suitable for a cat with renal failure stomach acid + cholangitis currently undergoing treatment + suspected IBD + amylase value 2400 on boodtest? coz…that’s my cat :/

    and coz of her whole host of problems, she can only eat small amounts at a time, so she asks for food every 2 hours. (yes, i get up a few times a night to feed her. i feel like the mother of a newborn baby). does this mean i just have to withhold feeding after giving her the enzymes?

  39. jhofve77
    January 5, 2011 at 3:17 pm

    The treatment takes 3 weeks; it may be into the last week to see improvement if it is a severe case.

  40. Monica
    January 4, 2011 at 9:10 pm

    How long before I see an improvement? I have had my kitten on this for 4 days and she still has very runny stool.

  41. jhofve77
    December 29, 2010 at 9:41 am

    As a veterinarian, I cannot comment on use of this protocol in humans. Physiologically speaking, I don’t know of any reason why it would not work the same way in any mono-gastric animals, including primates.

  42. Jo
    December 29, 2010 at 5:43 am

    Would taking digestive enzymes on an empty stomach 3 times a day work the same for humans with giardia or not?

  43. jhofve77
    December 22, 2010 at 8:03 pm

    Then you can use up to 1/4 tsp., just not with food. I say “up to” because there may be a limit to the cat’s tolerance! Get as much as you can into the kitty. There is no difference in dose between dogs and cats, and you can’t overdose.

  44. Jayne McIntyre
    December 22, 2010 at 2:54 pm

    The directions only state “Recommended serving is 1/4 Tsp. per cup of food.” These sound like directions for a dog too, as stated on the label “To improve nutrient absorption”. We are treating an 8 month old cat for Giardia that was diagnosed via stool sample. What would the dosage be as I what to follow the protocol you suggest in the above article.

  45. jhofve77
    December 21, 2010 at 7:35 pm

    Whatever the label recommends for your pet’s size.

  46. jayne mcintyre
    December 21, 2010 at 4:00 pm

    So I purchased the Prozyme as you suggested but it came in powdered form not capsules, so my question is how much powder do I use in each dose?

  47. jhofve77
    December 2, 2010 at 11:01 am

    The capsule is made of protein and will reduce the effectiveness of the treatment.

  48. LIla Ollmann
    December 2, 2010 at 8:28 am

    Is it necessary to make the slurry and use a syringe, or can you just give the cat the capsule? My cat seems to NOT have a problem swallowing the larger capsules, and she hates stuff given with a syringe. I’ve given her the whole pill for a day now. I suppose she could be digesting the capsule instead of the cysts. I didn’t think of that. ?

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